\Stalk"ing-horse\, n.
1. A horse, or a figure resembling a horse, behind which a
hunter conceals himself from the game he is aiming to
kill.
2. Fig.: Something used to cover up a secret project; a mask;
a pretense.
Hypocrisy is the devil's stalking-horse under an
affectation of simplicity and religion.
--L'Estrange.
How much more abominable is it to make of him
[Christ] and religion a stalking-horse, to get and
enjoy the world! --Bunyan.